Relationship between Canopy Closure and Pasture Production in Deciduous Tree Based Temperate Silvopastoral Systems

Relationship between Canopy Closure and Pasture Production in Deciduous Tree Based Temperate Silvopastoral Systems

Experiments were carried out in New Zealand with 11 year-old alder (Alnus chordata) on lowland pasture, and with 30+ year-old poplar (Populus spp) on hill pasture. Alder tree shade decreased (P< 0.001) tiller density and total herbage harvested, with the highest tiller density at the lowest shade level of 41% canopy closure (DifN 0.59). Net herbage accumulation (NHA) directly under a poplar canopy was 35% of the NHA of open pasture, but NHA in canopy gaps increased with gap size. These results suggested that keeping canopy closure percentage in the 40-50% range for a deciduous tree silvopastoral system, would maintain pasture production and tiller density at approximately two-thirds of that of unshaded pasture.